I will keep my order in place but if the camera does not show a large improvement over my E-520 in S-AF and C-AF it is going back and my 4/3rds lenses will be up for sale.

Pretty much everything I've read suggests that E-M1 focusing with 4/3 lenses will be about the same. In other words you are unlikely to see a "large improvement"!

Robin Wong:

“EXPECTATIONS VS REALITY”

"… the older Four Thirds DSLR lenses were running on a completely different system (Phase Detect AF), and even at their fastest and most efficient focusing, being mounted on the DSLR E-5 (which I am very familiar with), still falls behind the Micro Four Thirds' focusing speed. No Four Thirds lens previously had anything that can focus as fast as whatever the newer Micro Four Thirds lenses can do! I personally would love to have the older lenses miraculously perform as well as the Micro Four Thirds lenses in terms of AF speed, but let's face the reality: I have just established that it is not practical in any logical sense."

"… the Four Thirds lenses, even at their most efficient state, will not outdo the faster, newer and more technologically advanced AF system in the Micro Four Thirds lenses, …"